[clue-tech] Coffee shop wireless connection problem

[Matt Gushee]

Okay, last question for tonight.

I have this ASUS Eee netbook running Arch Linux (BTW, yeah, the keyboard 
is a bit small, but I love the extreme portability of it), which I use 
at various places around town. Now, it happens that at my favorite 
coffee shop I usually can't connect to the Net. I've spoken to the staff 
about it, and they are great people but not very technical: they know 
how to change the password and reboot the router, and that's about it. 
When that doesn't solve the problem, they call Qwest.

Now, I can't give many specifics, because (a) I don't have much 
information, and (b) it is not always the same problem. E.g., last month 
I could get connected to the access point and get an IP thru DHCP, but 
DNS wasn't working. With the help of Wireshark, I eventually figured out 
that it was an IPv6 issue, and disabling IPv6 solved that problem. Now I 
can't get an IP address. Since there are several other locations where I 
have no trouble getting connected, I don't think there's anything wrong 
with my hardware, and probably not with my software. And I have checked 
and rechecked multiple times that I have the correct password.

Anyway. What I am most interested in at this point is troubleshooting 
techniques. Given that my machine can see the access point, but I am 
either failing authentication or failing to get a DHCP lease, what if 
anything can I do to get more details about what exactly is happening?

Does it help if I say that: I am using wicd, mainly via the GUI, to 
manage connections? And that I have enabled its debug mode, but haven't 
seen any helpful log messages ("dhcpcd timed out" is typical). Also, my
kernel is 2.6.31, and Arch Linux has few if any distro-specific kernel 
patches. And my wireless controller appears to the system as a RealTek
RTL8187SE (rev 22).

TIA for all your tips.

-- 
Matt Gushee